Analisis Kualitas Air Menggunakan Makroinvertebrata sebagai Bioindikator di Sungai Namokarang Kecamatan Juhar Kabupaten Karo

Abstract

Macroinvertebrates are used as bioindicators because they live attached to the substrate and have low motility so they don't move easily. This study aims to analyze water quality using macroinvertebrates as bioindicators. This research was conducted in the Namokarang River, Juhar District, Karo Regency in September - November. Sampling of macroinvertebrates was carried out by purposive sampling where three station locations had been selected. Macroinvertebrate samples in the river were taken using a 30×30 cm surfer net with three replications. Based on the results of the study, the abundance values obtained at station I were 78 ind/m2, at station II 21 ind/m2, and 177 ind/m2 at station III. The value of macroinvertebrate diversity at each station was in the moderate category, where at station I was 1,447, at station II was 1,018, and station III was 1,445. Correlations between water quality parameters and macroinvertebrate abundance that showed a positive correlation were DO with very strong levels, moderate levels of temperature and turbidity, very low levels of brightness and TDS. While negatively correlated are the strong level of Depth, pH and N-total level of moderate relationship, Current and Phosphate with very low level. Correlations between water quality parameters and diversity of macroinvertebrates that show a positive correlation are temperature and DO at strong levels, N-total and brightness at low levels of TDS and Phosphate at very low levels while those that are negatively correlated are depth and very strong pH, currents (medium), Turbidity and Phosphate is very low. The pollution status of the Namokarang river based on the Pollution Index method is in the category of lightly polluted at stations I, II and good categories at station III. Calculation of the value of macroinvertebrate taxa using the SingScore method is in the "Very good" category.